A1 Certificate for Cross-Border Activities (Luxembourg/Germany)

The A1 certificate serves as official confirmation of which social security system applies to an employee engaged in cross-border activities within the EU.

Within the EU, the general principle is that only one Member State’s legislation may apply at any given time.

An A1 certificate is required in particular if employees:

• are temporarily working in another EU/EEA Member State or Switzerland (posting),
• travel abroad for business purposes, or
• regularly work in several countries (multi-state employment).

As a rule, the application must be submitted by the employer before the employee starts working abroad. Since 1 January 2025, A1 certificates in Germany must be applied for exclusively in electronic form; paper applications are no longer permitted.

The currently issued A1 certificates for your employees working in two or more Member States will expire soon and must be renewed in due time to ensure uninterrupted social security coverage.

We therefore kindly ask you to verify whether the information originally provided regarding the employee’s activities still reflects the actual circumstances or whether adjustments are required for a new A1 application.

Distinction Between the Different Cases When Applying for an A1 Certificate

1. Multi-State Employment Below the 25% Threshold

In straightforward cases where an employee mainly works in another country (e.g. Luxembourg) and performs less than 25% of their working time in their country of residence (Germany), the social security legislation of the country in which the employer is established generally applies.

Minor activities carried out in the country of residence do not usually result in a change of the applicable social security legislation. In such cases, the activities in the country of residence also remain subject to the social security system of the employer’s country.

In these cases, the application for the issuance of the A1 certificate is submitted to the Luxembourg social security authority (CCSS), which automatically forwards it to the German authority DVKA.

2. Framework Agreement for Cross-Border Telework Between 25% and 49.9%

The Framework Agreement on cross-border telework allows, in certain cases, for an exception agreement between the competent social security institutions. As a result, the social security legislation of the employer’s country may continue to apply.

Whenever an employee habitually works in several Member States — for example by regularly working from home in the country of residence — an A1 certificate is generally required.

Without a special exception agreement, the social security legislation of the country of residence generally applies if at least 25% of the overall activity is carried out there.

Therefore, if the share of activity in the country of residence is between 25% and 49.9% of the total working time, an exception agreement under the Framework Agreement must be requested in order for the social security legislation of the employer’s country to remain applicable.

Important:

Without a corresponding application and the subsequent conclusion of an exception agreement, the Framework Agreement does not apply. In such cases, the employee will generally become subject to the social security system of the country of residence.

Further general information is available from the German DVKA and the Luxembourg CCSS authorities. In cases of uncertainty, we recommend seeking individual legal advice.

Independent Application for A1 Certificates

Below the 25% Threshold

If you wish to apply for the A1 certificates yourself, we recommend the following procedure:

1. Application for an identification number (“Ordnungskriterium” / fictitious German tax number) for the Luxembourg company
2. Application for an ELSTER certificate
   (the identification number is mandatory for this step)
3. Registration with the fee-based social security reporting portal (“SV-Meldeportal”) using the ELSTER certificate

Once the initial registration with the SV-Meldeportal has been completed, future A1 certificates can easily be applied for electronically.

Should you have any questions regarding the above topics or if you would like us to prepare or submit the relevant applications on your behalf, we will be pleased to assist you at any time.

The above information is provided for general informational purposes only and does not replace individual legal advice in specific cases by a qualified attorney.

Status: 28 May 2026